Hi folks
Thought I'd add my 2cts and hope it's useful.
I've cloud flown a reasonable amount, mostly competitions,
all in the UK. Gliders cloud-flown include Vega, Bocian,
Duo, LS8, ASW27, ASW22, ASH25 and Nimbus4.

Regardless of the legal requirements, I’ve adopted
the following practical approach and it’s stood me
in good stead (I’m not an instructor, so you’ll have
to make your own minds up).

1) Minimum equipment (for me) is artificial horizon
and GPS. Everything else is merely desireable and I’ll
explain why.
Clouds are wet and cold. Eventually ice forms and your
ASI WILL be rendered useless (I have 2 pitots on the
Nimbus4, but both block within a few minutes of each
other). With no ASI (and no AH) then your T&S should
immediately be used to level up and LEAVE! IMHO it’s
a backup instrument in a glider.

2)Know where you are and heading. I've found that the
GPS provides very accurate direction whilst circling
(thermalling), albeit some 35 - 40 degrees behind for
direction. By commencing a levelling turn 40degrees
before desired heading, the final heading is achieved.
One can thereby change from thermalling to straight
flight pretty accurately. The compass is very difficult
to fly, with its progressing and recessing, but better
pilots than I use them regularly.

It often (usually) gets bumpy during the climb and
sometimes darn right turbulent. The cloud climb characteristics
seem to work through layers: The lift accelerates just
below cloudbase (latent heat of condensation) and the
'feel' often changes to slightly more active air (it
is)! This continues into the cloud (did I mention that
all radio calls, trimming, etc are done in the clear
below, leaving plenty of time to CONCENTRATE?).
The turn rate and trimming are already done and the
glider should pretty well fly itself hands off with
SMALL movements to counter any developing TRENDS.

Established in the circling climb, I scan the ASI,
cotton yaw string, horizon, GPS and VSI (keep reading
before you get overly excited - this is the PRACTICAL
approach). I look for the trend as much as the specific
value. If the AH shows the turn increasing, I take
off a little bank and vice versa. Sounds easy, but
of course as bank increases, the speed increases (back
to school) and when I unbank I need to push a little
to maintain speed. You'd be amazed how this basic becomes
difficult with a visual term of reference. Thermalling
the Nimbus in clear air, I aim for 57 knots for a reasonable
4knot climb. IN the cloud in the same thermal I expect
the climb rate to increase to closer to 6knots, but
I’ll let the speed vary from 50 to 65knots without
pulling or pushing too hard. Any more than that and
the flaps will have to go away. Small movements, anticipation,
look at the trend. OK, it’s going well, I’m 2000’ into
the cloud and lift improves to 8knots with a little
re-centering. Now the canopy is getting very wet and
that yaw string is glued and useless. However, it was
helpful to establish what ‘normal’ felt like and I
can now ignore it and scan the remaining instruments
(ASI, horizon, GPS and VSI) . It’s getting darker and
a little rougher. As the lift increased I had to allow
the glider to take a slightly higher attitude on the
AH to avoid excessive speed. Can someone explain that?
That means as the glider bounces out of the strongest
bit of lift I need to push quite positively and quickly
to avoid flying too slow. I use my bum to tell me when
the lift reduces or increases! VSI is too slow to respond.
The wings are very difficult to see now (I did an occasional
glance earlier when it was smooth) as ice starts to
cover the canopy inside and out. The ASI has packed
in, but that’s OK because I know what ‘normal’ looks
like on the AH. Instrument scan now AH, GPS, VSI. Lift
is now 9knots and still increasing. It’s getting colder,
I'm cold and forcing myself to relax on the stick,
but there’s a lighter patch on each revolution of the
turn that tells me I’m near the edge of the cloud.
Often the case higher up I’ve found, even if entering
the middle. The noise has increased. I particularly
notice it as I swallow and clear my ears in the 10knot
lift. It’s the ice forming on the wings. The controls
are sluggish and with my small anticipatory movements
the ice is slowly freezing the available movement in
the controls. I deliberately ‘stir’ the stick in a
quick wide circle to break free the controls. Time
to seriously consider leaving. I’ve been scanning the
GPS, so have a mental picture of which way ‘out’ or
the desired heading is. 40 degrees before heading I
bank over to level up, pushing quite positively. The
GPS is within 10 degrees (that will do) the AH is pretty
much there on the attitude and pretty level (my scan
is now AH and GPS only). It seems a bit slapdash maybe,
but keeping it within limits is the key. With 10knots
lift and now some 10,000’ extra height, flying precisely
is less an issue, flying safely is everything. More
turbulence as I fly along, but I resist the temptation
to push, pull or bank as my senses cry out. I only
follow the instruments and nothing else. Suddenly it’s
light, brilliant sun and I’m free. Check the horizon
(real) against the AH, but prepare to re-enter – keep
scanning in case it’s just a small gap. I keep a little
extra speed to compensate for the icy wings – just
a guess since the ASI is still frozen. I re-trim for
level flight. Finally clear, the view is stunning.
Another 5,000’ of cloud above, the ground a long way
down and a long glide beckoning into the warm air,
slower because of the ice, with occasional ‘stirs’
to keep the controls free.

I find that it’s a very useful skill that needs practice
and I do get rusty.
Most important of all, I practiced a ‘get out’. In
free air I experimented with various attitudes and
flap settings. For my Nimbus4 with the airbrakes extended,
flaps in neutral and the trimmer next to that funny
mark, controls held firm, the glider will eventually
recover from pretty much any attitude. I practiced
that in clear air, so I know it will work if I loose
it in the cloud. I just have to get the brakes out
before their limiting speed.

If the AH or electric fail (it’s happened to me) then
the AH flag will pop out and you’ve got a minute or
two to straighten and escape. This is when the T&S
comes into its own as a backup – to escape. The batteries
will get cold and don’t perform as well. Can;t have
too much power. Personally I don’t trust the new electronic
‘horizons’. I prefer a gyro that continues spinning
after the power fails.

With practice, one can centre and re-centre the climb
as the core moves. It needs a mental picture of the
turn and that’s where the GPS direction helps. It can
be a very rewarding experience, but best learnt in
a 2-seater with a grown-up! It’s a little scary at
first, but incredibly rewarding. Other factors include
temperature (yes I do use the guage), who's below,
who's nearby and whether the increased drag with wet
/ icy wings makes the whole exercise beneficial.

I wouldn’t try it in a thunderstorm!
Hope this helps – I await the flamers …
Pete Harvey